[llvm] [Support] Re-raise external signals (PR #125854)

[Fangrui Song via llvm-commits]

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@@ -80,7 +80,8 @@
 
 using namespace llvm;
 
-static void SignalHandler(int Sig);     // defined below.
+static void SignalHandler(int Sig, siginfo_t *Info,
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MaskRay wrote:

Drop unnecessary "defined below".

(If the declaration is unused, clang -Wall will report a warning.)

https://github.com/llvm/llvm-project/pull/125854